This study was conducted at the
Research Farm of the Abubakar Tafawa Balewa University, Bauchi, Nigeria to
investigate some factors (breed, season, parity, sex, litter size and body
condition score) affecting kids growth performance at various ages. The daily
weight gain (overall) of kids reveals non-significant breed effect whereas
season, parity, sex, litter size and body condition score had significant
(P<0.05) effects on the kids daily weight gain. Kids born in the dry season
had higher daily weight gain (98.95 ± 4.65g) than those born in the wet
season (88.15 ± 5.31g). Similarly, kids born in the second (90.58 ±
3.71g) and third (88.28 ± 11.31g) parities gained higher weights daily
than kids in the first (86.80 ± 3.25g) parity. There were significant
(P<0.05) sex and litter size effects on kids daily weight gain. The male
kids had higher daily weight gain than their female counterparts with
respective values of 92.94 ± 5.06 and 84.16 ± 5.46g. Similarly,
kids born single gained higher (90.06 ± 4.03g) daily weights than those
born as twins (87.04 ± 6.58g). Kids from does with body condition score
4 had the highest (91.61± 6.61g) daily weight gain followed by 3 (89.37 ±
5.37g) and least value was observed in does with score 2 (84.67 ±
4.95g). Kids weights at various ages (birth, 30, 60, 90 and 120 days) showed
significant (P<0.05) differences except for the effects of litter size (at
birth, 60,90 and 120 days) and sex (at 30, 60 and 120 days of life). Similarly,
kids mean daily weight gains at various age intervals (birth  30, 31- 60, 61-
90 and 91- 120 days) also showed significant (P<0.05) differences in these
factors except for the effects of breed (at 61-90 days), sex (at birth  60
days), litter size ( 61-10 days) and parity ( 31-120 days of life). It is,
therefore, concluded that large body size, good body condition, dry season,
birth of male kid and single birth and high parity resulted in higher postnatal
kid weight and daily weight gain. The Sahel goats are more promising than the
other breeds in terms of their growth performance. Improvement of these breeds
can be made through crossbreeding with better local or exotic breed. However,
these local breeds can be successfully used for quality meat production and
supply at an early stage of their life.

Key words: Goats,
age, daily weight gain

INTRODUCTION

Indigenous goats in Nigeria belong to three distinct breeds. The long-legged Sahel found in the arid and Sahel regions, the relatively small body-sized Red Sokoto found in the savanna zone and the
hardy, short-legged West African Dwarf restricted to high altitude areas and
humid forest of the south [1, 2]. Virtually all these breeds are found in Bauchi State, the study area. The Red Sokoto had the highest population followed by the
West African Dwarf and Sahel with least population [3]. The State being located
in the savanna zone the ecological niche of Red Sokoto. It is, therefore, expected
that the population of Red Sokoto goats will be high. The population of West
African Dwarf increases from the drier to wetter parts of the State.
Conversely, the Sahel goat population increases as one tended towards the
desert or drier parts of the State.

The breeding characteristics of
these animals in Bauchi are well documented in the literature [4, 5, 6]. It has
been reported that parameters such as litter size, birth weight and growth rate
of offspring from birth to weaning are some indices of reproductive performance
[7]. The reproductive function and capacity of goats in the tropics are
affected by several factors such as nutrition [8], season [3, 9], genotype [5,
10] and diseases [10, 11]. It has been shown that the low reproductive
performance of these animals in north-eastern Nigeria is implicated to the
traditional husbandry system, where no special care is given to the breeding
stock and hence their performance remains perpetually low [5].

However, the productivity of the
indigenous goats is generally low with respect to growth and lactation
performance. It is therefore imperative to understand and improve the growth
performance of these animals in this country in order to form a basis for rapid
controlled breeding programme. It is also necessary that any breeding programme
should always include the indigenous breeds since they possess some innate
resistance to certain local diseases in addition to adaptability to prevailing
climatic conditions. Improvement in these animals would go a long way towards
increased sources of quality and quantity meat and milk, which provide animal
protein that is indispensable to a balanced human diet. It has been reported that
goat meat or chevon is widely accepted in the country and has wide
acceptability among the different socio-cultural groups because there is a lack
of taboo against chevon [12]. It has also been reported that the milk from
goats has special characteristics such as high digestibility, distinct
alkalinity and therapeutic uses in medicine [13]. For instance, goat milk has
been shown to be tolerated by children and infants suffering from
hypersensitivity to cow milk [14]. However, the small size of goats relative to
cattle and other farm animals contributes to their wide distribution and ease
of management among women and children who provide the bulk labour in small
family farms [15]. Goats have important drought survival strategy in marginal
cropping areas where mixed farming is prevalent [16]. Also, goats serve as an
insurance against crop failure because they are liquid asset [15].

Performance of these three
recognized indigenous goats with respect to differences in breed, body
condition score, season, sex, litter size and parity is practically
non-existent in literature. Therefore, this study was designed to investigate
the pattern of growth and development in these species in Bauchi with the hope
of providing baseline information for improvement in their growth traits.

MATERIALS AND METHODS

Location and climate

Bauchi metropolis, the study
area, apart from being the State capital and headquarters of Bauchi Local
Government, is also the main urban centre in the State. It is situated on
latitude 10° 17I north, longitude 8° 49I
east and at an altitude of 690.2 metres above sea level in the northern guinea
savannah ecological zone of Nigeria [17].

Experimental goats

The breeds of goat used for the
study were the Red Sokoto (RS), Sahel (SG) and West African Dwarf (WAD). A
total of 43 goats including two bucks per breed constituted the initial stock.
The bucks were used for within breed natural mating on the nulliparous does
aged one-year. The composition of does at the beginning of fertility trial was
15 RS, 12 SG and 10 WAD. These does were used to produce the offspring (kids)
on which records were taken.

Goat management

The animals were managed
semi-intensively. In the night, they were kept in cross-ventilated pens within
the animal house but allowed to graze during the day within the University
premises. They were supplemented with mineral licks and concentrate; a mixture
of poultry litter, maize offal and rice bran in 1:2:1 ratio (18% crude
protein). At times they were also fed groundnut haulms. Routine health care
practices such as vaccination/medication, ecto-parasite control and de-worming
were also regularly carried out. Fresh drinking water was provided ad
libitum. The animals were also kept for three weeks to acclimatize before
the commencement of the study.

Data collection

Data for this study were
collected on-station from October 2003 to May 2006. The age of the goats was
determined by dentition method as reported by Butswat [4]. Does and their kids
were weighed using a bathroom scale. Body condition score was also determined
as per the procedures laid down by Jefferies [18]. Breeding was monitored up to
third parity using within breed mating. All does were hand-mated. Kids weights
at various ages (0, 30, 60, 90 and 120 days) and the dams parity were
recorded. Growth rates from birth to 30, 31  60, 61  90 and 91  120 days of
life were also determined using the following relationship reported by
Malau-Aduli et al. [19].

Data analysis

The data generated were subjected
to analyses of variance, correlation and regression using the General Linear
Model (GLM) of SPSS (2001). Means were subsequently separated using Duncan
Multiple Range Test (DMRT) method described by Humburg [20].

RESULTS

The daily weight gain of kids
reveals non-significant breed effect whereas season, parity, sex, litter size
and body condition score had significant (P<0.05) effects on the kids daily
weight gain. Kids born in the dry season had higher daily weight gain (98.95 ±
4.65g) than those born in the wet season (88.15 ± 5.31g). Similarly,
kids born in the second (90.58 ± 3.71g) and third (88.28 ±
11.31g) parities gained higher weights daily than kids in the first (86.80 ±
3.25g) parity. Kids from does with body condition score 4 had the highest
(91.61± 6.61g) daily weight gain followed by 3 (89.37 ± 5.37g)
and least value was observed in does with score 2 (84.67 ± 4.95g). There
were significant (P<0.05) sex and litter size effects on kids daily weight
gain. The male kids had higher daily weight gain than their female
counterparts; with respective values of 92.94 ± 5.06 and 84.16 ±
5.46g.Similarly,kids born single gained higher (90.06 ± 4.03g) daily
weights than those born as twins (87.04 ± 6.58g) (Table 1).

Kids weights at various ages
(birth, 30, 60, 90 and 120 days) as influenced by breed, body condition score,
season, sex, litter size and parity are shown in Table 2.The SG does had the
largest weight at birth (1.91 ± 0.01kg) followed by RS (1.76 ±
0.01kg) which were significantly (P<0.001) higher than that of WAD (1.65 ±
0.01kg). This superiority was maintained through 30, 60, 90 and 120 days of age
.The weight superiority as applied to kids from does with different body
condition scores were (4> 3>2), parity (3>2>1) and season (in
favour of the dry season). These superiorities (P<0.001) were sustained up
to day 120 of age. However, while male kids were superior (P<0.05) at birth,
at 30 and 60 days there was similarity in the weight of the two sexes. At 90
days of age male kids were again heavier then and there was similarity in weight
gain at 120 days. The influence of litter size at birth on kid weights differed
non-significantly but at the age of 30 days kids born single became
significantly (P<0.05) heavier than twins.

Kids mean daily weight gains
(growth rates) at various age interval (birth to 30, 31-60, 61-90 and 91-120
days) as influenced by breed, body condition score, season, sex, litter size
and parity are presented in Table 3. The results show that daily weight gain
was significantly affected by breed from birth to 30 day (P<0.01), 31-60
days (P<0.05) of age. The RS and SG kids were superior to their WAD
counterparts during these intervals. However, during 61-90 days the three
breeds did not differ significantly, but from 91 to 120 days the RS kids were superior
(P<0.01) to SG and WAD kids. The does body condition scores had pronounced
effect on daily weight gain of kids at the various age intervals. For instance,
kids from does with body condition scores 3 and 4 were superior (P<0.05) to
kids from does with score 2 at birth to 30, 31- 60 and 91-120 days of age. However,
there was significant (P<0.05) seasonal influence on kids daily weight gain
at birth to 30 and 91- 120 days of age only; with kids born in the dry season
being favoured. Similarly, male kids were only significantly (P<0.05) better
than their female counterparts at 61-90 (P<0.01) and 91-120 (P<0.05) days
of age as shown in Table 3. Kids born single gained more weight daily than
twins at birth to 30 and 31-60 days of age (P<0.05). There was, however, no
significant difference in the daily weight gains of kids born single or twins
from 61 to 120 days of life. Conversely, kids from second and third parities
were superior (P<0.001) to their counterparts in daily weight gain only from
birth to 30 days of age.

There were significant
correlations (P<0.05  P<0.001) between some of the goat traits and daily
weight gain of kids. For instance, there were high and positive correlations
between litter size versus body condition score (r = 0.25) (P<0.05), age versus
weight (r = 0.97), age versus daily weight gain (r = 0.63) (P<0.01).
However, there were also low and negative correlations between litter size versus
weight (r = -0.12), litter size versus daily weight gain (r = -0.12)
(P<0.05) and weight versus daily weight gain (r = -0.50) (P<0.01). Table 4 shows the regression equations of weight and daily weight gain versus age in
the three breeds. In RS, SG and WAD goats, the variations in weight of kids due
to age were 95.3, 95.2 and 94.6 % respectively. Similarly, the variations in
daily weight gain of kids due to age were 28.0, 52.6 and 41.8% for RS, SG and
WAD respectively.

DISCUSSION

The initial kid weight (birth
weight) observed in this study is higher than the values reported by Adama and
Arowolo [21] in Savanna Brown kids but lower than the findings of Nkungu et
al.[22] in Norwegian goats and their crosses in Tanzania. This study also
observed significant breed effect on kid weight at various ages. The SG kids
had the highest initial weight followed by RS. The weight superiority was
maintained at various ages up to weaning age (4 months). Superiority in growth
performance of RS over WAD kids at 12 month of age had been reported [23].
Superiority from 75 and 50% Norwegian crosses as compared to 100 and 87.5%
Norwegians had been observed by Nkungu et al.[22]. Superior weight in RS
(11.53kg) over WAD (8.78kg) kids at weaning and attributed it to genotype as
observed in the study reported by Butswat et al. [5].

Kids from does with good body
conditions tended to be superior in weight during all stages of life. It has
similarly been observed by Malik et al.[24] that weight of does at
kidding influenced kids birth weights positively. It has also been reported
that weight of kids at weaning was significantly higher (6.53kg) in does with
body condition score 2 than those with body condition score 1 (3.05kg) [25].

Kids born in the dry season were
superior to their counterparts in the wet season in terms of initial weight.
This weight advantage was consistently maintained up to the weaning age of four
months. This superiority is mainly attributed to the fact the wet season is
characterized by many growth-limiting factors; the restriction imposed due to
farming activities, high incidence of pests and diseases and the interplay and
influence of climatic factors. It has also been observed that climatic factors
influence greatly the productivity of goats especially under traditional system
of management through their effects, principally on forage, water availability,
thermal stress and photoperiod which are reflected in seasonal trends in
growth, reproduction and morbidity [4]. However, it is reported that kids
survived best and weaned at 3 months after birth during the dry season [25]. This
difference was probably attributed to fewer incidences of pests and diseases in
the dry than in wet season. It has also been observed that weaner does fed
concentrate at 2% of body weight attained puberty at earlier ages and heavier
body weight than does fed concentrate at 1% body weight [19]. These workers
also stated that the purpose of proper management of a young male animal is to
improve growth performance and to enable them produce optimum levels of good
quality semen at the earliest possible age.

Male kids weighed more than
females kids at birth and were heavier at various ages up to 120 days. This
agrees with the findings of Nkungu et al.[22] who observed that male
kids were superior to their female counterparts at all stages of growth up to
12 months. Similarly, the male kids of Savanna Brown goats had consistent
weight advantage over the females at various ages up to 100 days [21]. It has
been attributed that the growth superiority of male kids to higher birth weight
and presence of androgens, which play a role in growth [22, 26]. These workers
further stated that the superiority may also be due to the fact that males are
more aggressive and active than females, and may consume more milk and feed.
The difference between male and female kids may also be reflected in attainment
of puberty. It has been observed that the onset of puberty is more closely
related to body weight than age [27]. This means that male or female kids from
SG goats may reach puberty at relatively younger age than the other indigenous
goat breeds of the same sex and other management practices.

The study observed that kids born
single were non-significantly heavier than their twin counterparts (at 30 days
of age and thereafter) the non-significant difference resumed. The growth
performance of kids born single was higher than twins at various ages [28, 29].
These workers attributed the weight advantage to competition for nutrients
(milk) and the less inter-uterine space in cases where does carry two or more
foetuses as compared to one.

This study observed that kids
from lower parities had significantly lower weights at different ages, than
third parity kids. This superiority was consistently maintained up to weaning
at 120 days of age. This might have been due to increase in doe body weight
with advance in parity or age, which reflected on kids. It has been similarly
observed by Bemji et al. [30] that live weight of kids significantly
increased with parity of does.

The RS and SG were similar in
daily weight gains, but significantly higher than WAD at the various age intervals.
Significant (growth rate) daily weight gain difference at various ages of Norwegian
kids crosses (100, 87.5, 75 and 50%) have been reported, and was attributed to
inherent live weight differences [22].

Kids from does with good body condition
score had significantly higher daily weight gain at various ages than those
with lower body scores. Good body condition is a reflection of good nutrition
and hence adequate body tissue reserves for normal functions of the body.
Nutrition has a great influence on the reproductive performance of sheep, which
differ, to some extent from goats [31]. It has been shown that parameters such
as litter size, birth weight and growth rate of offspring from birth to weaning
are indices of reproductive performance [7].

This study observed that the dry
season kids had significantly higher daily weight gain than wet season kids
from birth to 30 days of age, and subsequently (from 31-90 days) there was
non-significant difference until 91-120 days of age when the wet season kids
had significant weight advantage over the dry season counterparts. This
difference in the daily weight gain of dry and wet season kids might have been
due to the dynamics of feed or nutrient supply and availability to the animals
and their freedom to roam and fend for themselves. It has been reported that
the weights of goats were highest during the early rainy seasons, while the
least weights were obtained during the late rainy season [4].

The study observed
non-significant sex effect on daily weight gain of kids from birth up to 60
days of age. A similar observation has been made by [21] in Savanna Brown kids
from birth to 100 days of age. The finding of this study however contradicts
the findings of [22] who reported that female kids had higher daily weight gain
from birth to 3 months of age. The present study observed significant sex
effect on daily weight gain from 61-120 days in favour of male kids. This
agrees with the observation made by Nkungu et al.[22] that there was
consistently higher weight gain advantage in male than in female kids from 3 to
12 months of age.

Significant litter size effect
was observed on daily weight gain of kids from birth to 60 days of age and in
favour of kids born single. This contradicts an earlier study by Adama and
Arowolo[21] that single male, single female, twin male and twin female kids
differed non-significantly in terms of daily weight gain from birth to 100 days
of age. However, this study agrees with the reports by Nkungu et al. [22]
that kids born single were superior to their counter parts born twins in daily
weight gain from birth to 12 months of age. The consistent daily weight gain
advantage (in favour of kids born single) may be linked to pre-and-early
post-natal nutrient competition and the less inter-uterine space the twin kids
experienced.

Significant parity effect was
also observed in the study with respect to kids daily weight gain. From birth
to 30 days of age, the daily weight gain increased significantly with parity,
and subsequently (from 31 to 120 days) the difference remains unchanged
statistically in the three parities. This observation could be linked to the
explanations given by Bemji et al.[30] that live-weight of does
increased significantly with parity which reflected on the birth weights of
their kids. This should also have effect on their early growth rate.

Some prediction equations
obtained in this study were significant and had large coefficient of multiple
determination (R2). The high percentage R2 _ are
indications that the weight changes of kids were mainly attributed to age. On
the other hand, the lower percentages R2_values are indications that
a lot of the variations in kids daily weight gain were due to other causes.
That is, the high R2_values for some equations indicate their
ability to predict kid body weights and daily weight gains at various ages
accurately as opposed to low R2 values. A similar report has been
made by Akanno and Ibe [32]. They further stated that this tool (regression
equations) could be valuable in some rural African farm communities where
sensitive weighing scales are not readily available in the market and if
available are expensive. Animal dentition could be applied to obtain age (if
done accurately), which in turn could be used to predict live weight or daily
weight gain.

Improvement in performance of
growth traits in this species and probably in other farm animal species will
help in no small measure in enhancing the protein production, supply and
consumption by the populace. It has been reported that good nutrition is a
prerequisite for good health, reproduction and fast growth rate in individuals
[33].

CONCLUSION

Based on the results of this
study on kids growth performance, it is concluded that large body size, good
body condition score, dry season, birth of male kid and single birth and high
parity resulted in high post-natal kids weight and daily weight gain. These in
turn lead to increased performance in terms of improved birth and weaning
weights, survival rates of kids at various ages of life and early attainment of
age at puberty, improved reproductive make-up of kids at commencement of
reproduction, substantial improvement in milk yield in kids that grow to does
in their first and subsequent parities, increased immunity and minimal
incidence of diseases and pests among kids, increased meat/protein production
at an early stage of life and increased income supply of the farmer.

Butswat
ISR, Sir SM and SU Gwani Reproductive performance of small ruminants under
the traditional management system in north-eastern Nigeria. Proceedings of the
Silver Aniversary Conference of Nigerian Society for Animal Production |(NSAP)
held at University of Agriculture, Abeokuta, Nigeria, 1998:532-533.

Zahraddeen
D, Butswat ISR, Abdulkarim M, Mancha YP and D Yande Birth weights and
weaning weights of West African Dwarf lambs and kids under small holder
husbandry system in guinea savannah zone of Nigeria. Proceedings of the 32nd Annual Conference of Nigerian Society for Animal Production (NSAP) held at the
University of Calabar, Nigeria. 2007: 95.